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Supernova Nucleosynthesis and Extremely Metal-Poor Stars

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 نشر من قبل Nozomu Tominaga
 تاريخ النشر 2008
  مجال البحث فيزياء
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We investigate hydrodynamical and nucleosynthetic properties of the jet-induced explosion of a population III $40M_odot$ star and compare the abundance patterns of the yields with those of the metal-poor stars. We conclude that (1) the ejection of Fe-peak products and the fallback of unprocessed materials can account for the abundance patterns of the extremely metal-poor (EMP) stars and that (2) the jet-induced explosion with different energy deposition rates can explain the diversity of the abundance patterns of the metal-poor stars. Furthermore, the abundance distribution after the explosion and the angular dependence of the yield are shown for the models with high and low energy deposition rates $dot{E}_{rm dep}=120times10^{51} {rm ergs s^{-1}}$ and $1.5times10^{51} {rm ergs s^{-1}}$. We also find that the peculiar abundance pattern of a Si-deficient metal-poor star HE 1424--0241 can be reproduced by the angle-delimited yield for $theta=30^circ-35^circ$ of the model with $dot{E}_{rm dep}=120times10^{51} {rm ergs s^{-1}}$.



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